scholarly journals Internal Structures of Known Pinctada Maxima Pearls: Cultured Pearls from Operated Marine Mollusks

2021 ◽  
Vol 57 (3) ◽  
pp. 186-205
Author(s):  
Artitaya Homkrajae ◽  
Nanthaporn Nilpetploy ◽  
Areeya Manustrong ◽  
Nicholas Sturman ◽  
Kwanreun Lawanwong ◽  
...  
Minerals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 357 ◽  
Author(s):  
Stefanos Karampelas ◽  
Fatima Mohamed ◽  
Hasan Abdulla ◽  
Fatema Almahmood ◽  
Latifa Flamarzi ◽  
...  

The present study applied Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) on a large number of natural and cultured pearls from saltwater and freshwater environments, which revealed that freshwater (natural and cultured) pearls contain relatively higher quantities of manganese (Mn) and barium (Ba) and lower sodium (Na), magnesium (Mg) and strontium (Sr) than saltwater (natural and cultured) pearls. A few correlations between the host animal’s species and chemical elements were found; some samples from Pinctada maxima (P. maxima) are the only studied saltwater samples with 55Mn >20 ppmw, while some P. radiata are the only studied saltwater samples with 24Mg <65 ppmw and some of the P. imbricata are the only studied saltwater samples with 137Ba >4.5 ppmw. X-ray luminescence reactions of the studied samples has confirmed a correlation between its yellow-green intensity and manganese content in aragonite, where the higher Mn2+ content, the more intense the yellow-green luminescence becomes. Luminescence intensity in some cases is lower even if manganese increases, either because of pigments or because of manganese self-quenching. X-ray luminescence can be applied in most cases to separate saltwater from freshwater samples; only samples with low manganese content (55Mn <50 ppmw) might be challenging to identify. One of the studied natural freshwater pearls contained vaterite sections which react by turning orange under X-ray due to a different coordination of Mn2+ in vaterite than that in aragonite.


2008 ◽  
Vol 31 (1) ◽  
pp. 15-21 ◽  
Author(s):  
U. Wehrmeister ◽  
H. Goetz ◽  
D.E. Jacob ◽  
A. Soldati ◽  
W. Xu ◽  
...  

2021 ◽  
Vol 57 (1) ◽  
pp. 2-21
Author(s):  
Artitaya Homkrajae ◽  
Areeya Manustrong ◽  
Nanthaporn Nilpetploy ◽  
Nicholas Sturman ◽  
Kwanreun Lawangwong ◽  
...  

Author(s):  
Å. Thureson-Klein

Giant mitochondria of various shapes and with different internal structures and matrix density have been observed in a great number of tissues including nerves. In most instances, the presence of giant mitochondria has been associated with a known disease or with abnormal physiological conditions such as anoxia or exposure to cytotoxic compounds. In these cases degenerative changes occurred in other cell organelles and, therefore the giant mitochondria also were believed to be induced structural abnormalities.Schwann cells ensheating unmyelinated axons of bovine splenic nerve regularly contain giant mitochondria in addition to the conventional smaller type (Fig. 1). These nerves come from healthy inspected animals presumed not to have been exposed to noxious agents. As there are no drastic changes in the small mitochondria and because other cell components also appear reasonably well preserved, it is believed that the giant mitochondria are normally present jin vivo and have not formed as a post-mortem artifact.


Author(s):  
George Hug ◽  
William K. Schubert

A white boy six months of age was hospitalized with respiratory distress and congestive heart failure. Control of the heart failure was achieved but marked cardiomegaly, moderate hepatomegaly, and minimal muscular weakness persisted.At birth a chest x-ray had been taken because of rapid breathing and jaundice and showed the heart to be of normal size. Clinical studies included: EKG which showed biventricular hypertrophy, needle liver biopsy which showed toxic hepatitis, and cardiac catheterization which showed no obstruction to left ventricular outflow. Liver and muscle biopsies revealed no biochemical or histological evidence of type II glycogexiosis (Pompe's disease). At thoracotomy, 14 milligrams of left ventricular muscle were removed. Total phosphorylase activity in the biopsy specimen was normal by biochemical analysis as was the degree of phosphorylase activation. By light microscopy, vacuoles and fine granules were seen in practically all myocardial fibers. The fibers were not hypertrophic. The endocardium was not thickened excluding endocardial fibroelastosis. Based on these findings, the diagnosis of idiopathic non-obstructive cardiomyopathy was made.


Author(s):  
Philippa Smethurst

This is a reflection on the power of endings and time boundaries, exploring the way that time can act as a catalyst in psychotherapeutic processes. The article describes the ending processes with five clients. These occurred simultaneously due to the author’s relocation. Some responses illuminate hitherto hidden and intractable internal structures, and in others the intensity of the limit acts an impetus for the client to grasp something new. Drawing on Power’s comprehensive book: Forced Endings in Psychotherapy and Psychoanalysis (2016), the author reflects on the power and energy springing from the setting of the time boundary and the different dynamics created in client and therapist. There is acknowledgement of the pressure that this can create in the therapist and also there are reflections about what ultimately may be achieved.


2019 ◽  
pp. 4-44 ◽  
Author(s):  
Peter Thorns

This paper discusses the organisations involved in the development of application standards, European regulations and best practice guides, their scope of work and internal structures. It considers their respective visions for the requirements for future standardisation work and considers in more detail those areas where these overlap, namely human centric or integrative lighting, connectivity and the Internet of Things, inclusivity and sustainability.


2001 ◽  
Vol 23 (2) ◽  
pp. 119-139
Author(s):  
R. A. GREGORY ◽  
D. W. HALL ◽  
D. W. SHIMWELL

Excavation at a crop-mark site found close to Annan, Dumfries and Galloway, revealed evidence of a ring-ditch containing a number of intriguing internal structures. Initially this was presumed to be a prehistoric monument, but pottery and radiocarbon dating, unexpectedly, indicated that the main structural phase of the site falls between the 11th-13th centuries AD. This suggests that a degree of caution is required when interpreting crop-mark sites on morphological characteristics alone. Moreover this excavation makes clear that morphological interpretation can have a constraining influence on excavation strategy, so caution is required when designing fieldwork programmes.


2019 ◽  
Vol 36 (8) ◽  
pp. 706-708
Author(s):  
Thanh Nhan Bui ◽  
Sophie Leblan ◽  
Aurélien Delaunay
Keyword(s):  

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